Japanese researchers are working on a robot they hope will be smart enough to ace entrance exams at the nation's top university, which test everything from maths to foreign languages.

The robot's artificial brain would analyse a mash of words, numbers, and equations before spitting out the -- hopefully -- correct answer to questions on Tokyo University's notoriously tough exam.

"It has to analyse the exam questions and convert formulations and equations to a form that it can process before solving it through computer algebra," said Hidenao Iwane from Fujitsu Laboratories, the Japanese IT giant's research unit.

Fujitsu and Japan's National Institute of Informatics said the target is to have their robot score high marks on the exam for Tokyo University, one of the world's top-ranked schools, by 2021.

Before then, they're hoping the robot can sail through national entrance exams which all university-bound students must take in Japan.

The ultimate goal is to develop technology that would "enable anyone to easily use sophisticated mathematical analysis tools", Fujitsu said.

"(But) getting a computer to understand text that was intended for humans is not an easy task," it added.